Comparison of GIMMS and MODIS normalized vegetation index composite data for Qinghai-Tibet Plateau. Net primary productivity (NPP) of grassland ecosystem and its relationship with climate in Inner Mongolia Analysis of vegetation dynamics using GIMMS NDVI3g in the Three-Rivers Headwater Region from1982 to 2012 Spatio-temporal patterns and driving factors of vegetation growth anomalies in Xinjiang over the last three decades